package com.wlanauth.core.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/**
 * MD5加密
 * @author zz
 * @date 2012-7-2
 * @email charles.zz.life@gmail.com
 */
public class MD5Util {
	
	public static String encode(String s) {
		try {
			return encode(s.getBytes());
		} catch (Exception e){
			throw new RuntimeException(e.getMessage(),e.getCause());
		}
	}
	public static String encode(byte[] bytes) throws NoSuchAlgorithmException{
		MessageDigest digest = MessageDigest.getInstance("MD5");
		char hexDigits[] = { '0', '1', '2', '3', '4',
                 '5', '6', '7', '8', '9',
                 'A', 'B', 'C', 'D', 'E', 'F' };
		byte[] md = digest.digest(bytes);
		//把密文转换成十六进制的字符串形式
        int j = md.length;
        char str[] = new char[j * 2];
        int k = 0;
        for (int i = 0; i < j; i++) {
            byte byte0 = md[i];
            str[k++] = hexDigits[byte0 >>> 4 & 0xf];
            str[k++] = hexDigits[byte0 & 0xf];
        }
		return new String(str);
	}

}
